A Cursed Sword
by Silvers88
Summary: In a Unforgiving world, Kiritsugu must make a choice. Does he choose to take Shirou's training seriously in magecraft to protect him from the dangers of the moonlit world or does he choose to hide him away and hope things work out. Unfortunately one of those options is too unrealistic to work. With the help of an old acquiescence, Shirou will be ready for whatever is thrown at him.


**Prologue: Professional Courtesy**

 **Disclaimer: I don't own Fate/Stay Night or anything related to it**

Out of all the decisions Kiritsugu has made, this is by far one of the toughest he's encountered. Watching his adopted son Shirou practice what little magecraft he's learned so far, he couldn't help but feel guilty for what he's considering.

Throughout his life, Kiritsugu has sacrificed everyone and everything he had to in order to save as many people as possible. He killed his own father for the experiments that lead to the extermination of an entire island. He has sacrificed his adopted mother, wife, and partner and gave up any chance to see his daughter again all in order to save the world from Angra Mainyu's curse. And all that he has to show for his sacrifices are countless unmarked graves of those he's killed and a curse that is slowly killing him.

Despite everyone that he's saved, the only person that he has ever truly saved is Shirou. In the aftermath of the Fourth Holy Grail War, the destruction of the Holy Grail lead to the infamous fire that killed many people in Fuyuki. The sight alone was more than enough to leave Kiritsugu broken. He wandered around for what felt like hours searching for anyone to save. After combing through all the corpses, Kiritsugu had found Shirou. He was so happy that he broke down crying tears of joy.

After some time in the hospital, Shirou was adopted by Kiritsugu and they started living together as a family. With time, Shirou had managed to convince his adopted father to teach him some magecraft. While Shirou has absolutely no natural talent in magecraft, the boy is persistent and a fast learner. After a couple weeks of practice he had managed to learn how to properly use his magic circuits.

Seeing the accomplishment reminded Kiritsugu of when he started training under Natalia. That was the first step in what lead Kiritsugu to becoming the Magus Killer, the unofficial boogey man of the moonlit world.

Throughout his blood-filled career hunting down Magi, Sealing Designates, and Dead Apostles, he had become one of the most feared men alive in his era. The mere mention of his moniker was enough to fill most with dread. He was efficient, calculated, and willing to do whatever necessary to kill his target.

Because of how good he was at his job and how long he was active, Kiritsugu has made many enemies. Magi are a lot of things, but forgiving and forgetful they are not. Most Magi around the world wouldn't hesitate to kill as many people as necessary to gain what they want, regardless of how miniscule it is. Most wouldn't hesitate to spend years torturing someone for the sake of their research. Most Magi aren't above revenge and wouldn't hesitate to hold a grudge throughout multiple generations of their family.

Thanks to Angra Mainyu, Kiritsugu was cursed to die no matter what. The fear of a slow painful death doesn't mean much to a dead man. However, Magi aren't above seeking revenge elsewhere. And that's what scared Kiritsugu most.

Illya is safely hidden away in the Einzbern castle. No magus would dare attack that castle so long as Acht is still around. But that left Shirou. The moonlit world at large believes Kiritsugu to have died during the Fourth Grail War. Most magi are foolish enough to believe that rumor without seeking any kind of proof.

However, the ones that want revenge the most are the same ones who will want to verify the Magus Killer's death. Acht will settle for keeping Kiritsugu as far away from his daughter as possible. But various families within the Clocktower and various mercenaries and dead apostles want his corpse to claim they've killed the infamous Magus Killer. If they can't get him, they'll take Shirou and either torture and kill the boy or sell him off to someone else will do unthinkable things.

Thanks to the curse that is killing him, Kiritsugu can't protect his son forever. His body has already deteriorated so much that he can barely do a fraction of the things he was once able to. At most, he has a few years of life left. Even then, that's mostly hopeful speculation

There's a chance that Shirou could live the rest of his life and remain fine. Most magi tend to stay away from Asia, even more so from Japan. Additionally, magi absolutely refuse to use any kind of modern technology. If they did, finding the Magus Killer and his son would be a much simpler task. Granted, it still wouldn't be easy but it would still be far more possible.

Throughout his life, Kiritsugu has learned one definitive truth. Fate is an asshole. Leaving things up to fate is a recipe for disaster. No matter the job, Kiritsugu does everything he can to mitigate fate as much possible. Any mercenary worth their salt knows any unknown variable has the potential to get them killed.

That is where Kiritsugu is conflicted. One part of him wants to spare Shirou from the moonlit world. He wants nothing more for his son than live a peaceful and normal life. But doing that will require him to convince Shirou to give up magecraft. The problem with that is if someone does learn of who Shirou is, he has no way of protecting himself. He'll be leaving his son to suffer a horrible death. Shirou is an honest boy and looks up to Kiritsugu, the redhead would never lie about who his father is.

The other part of him wants to train Shirou in everything he knows about magecraft, fighting, and tactics. Doing so will give his son the tools he needs to protect himself. The problem is that Shirou idolizes him. Kiritsugu has told his son about his desire to save everyone he could and that inspired Shirou to want the same thing. That meant that training Shirou would be the same thing as damning the boy to eventually share his fate. To suffer a life full of death and loss where all that's left in the end is regret.

Seeing Shirou drop to the ground in exhaustion, Kiritsugu knew what he was going to do. The biggest problem is that he can't do it alone, he need help. "Shirou, that's enough for tonight," Kiritsugu said as he helped his son to his feet.

"Ah man, can't I just have a little more time? I've almost managed to trace this knife." Shirou pleaded as he held onto the flawed copy of a pocket knife he's been working on.

"You've been at it for hours now. You're still young; you have more than enough time to learn how to trace." Kiritsugu said, giving his son a reassuring smile. Hearing his words caused Shirou to relent, albeit slightly begrudgingly.

As Shirou walked into the house, Kiritsugu examined the knife Shirou had been trying to trace. The original copy of the pocket knife is of relatively simple design with a few basic runes inscribed into it. The copy Shirou was working on had a few flaws but was a decent copy for someone so young that doesn't have any natural skill. What did catch Kiritsugu's eye the though was the quality of the blade.

The blade was copied almost perfect, the runes that maintained the quality and sharpness had some discrepancies but were acceptable. The handle and the runes inscribed into it could use some work. Not bad for a beginner, but there's still a lot of room for improvement.

At least he has an idea of what he'll need to work on. Well, that's a problem for another time.

The following morning, Kiritsugu walks into the dining room wearing a black suit and sees Shirou in the kitchen cooking breakfast and Taiga already sitting at the table whining as she waits for breakfast. Cooking has been one of Shirou's favorite things to do outside of training in magecraft. Kiritsugu couldn't understand where his love for cooking came from but he was thankful for it. The Magus Killer could only make MREs and even then that was iffy. Even making a bowl of cereal was almost too complicated.

"Morning Shirou, Taiga," Kiritsugu said as he sat at the table.

"Morning. Good timing, I just finished making breakfast." Shirou said as he brought everyone their food. Noticing how his father dressed, Shirou couldn't help but frown. "Are you leaving to go on another trip?" Shirou asked, already knowing the answer. Since they've been living together, Kiritsugu had a tendency to leave for months at a time to go on what his father called 'business trips'. Every time he came back, Kiritsugu would always either looking sick or sad. Whenever Shirou asked his adopted father where he went, Kiritsugu would always change the subject.

"Yes, though I won't be gone for long. I should only be gone for a couple weeks this time." Kiritsugu said, raising Shirou's spirits and curiosity.

"Really? Where are you going?" Shirou asked.

"I'll be visiting an old acquaintance. Now, let's hurry up and eat before Taiga eats everything." Kiritsugu said as he quickly grabbed what food he could, while he likes having Taiga around since she reminded him of an old friend, he knew better than to get in between her and food.

Silently agreeing, Shirou mimicked his father's actions. Last time he tried to get in between Taiga and food, she bit him. In Taiga's defense, Shirou should have known better.

 **Time Skip**

The world is full of places for people to disappear. Some people preferred warmer tropical islands while others preferred snowy mountainsides. Personally Kiritsugu preferred the weather in Japan. The dry arid environment of Cairo was just too hot for his liking, especially since his usual taste in fashion includes wearing all black.

Walking through the back streets, the former Magus Killer knew where he was going. And unfortunately for him so did the people that were watching his every movement. Kiritsugu knew he was being watched but did nothing to disappear from their gaze. That would send the wrong message and make things more complicated.

Approaching a bar, Kiritsugu took a deep breath as he walked through the doors. Upon looking inside, he could see that the bar was a surprisingly lively place given how difficult it is to reach. Taking a seat at a table in the back, Kiritsugu waits patiently.

"Tell me if you heard this joke, a dead man walks into a bar," a male voice said, taking a seat at the table behind the magus killer. Neither of the men were looking at each other yet they were well aware of the subtleties in how each other were sitting. They just sat there waiting to see how thing would turn out.

"When a ghost story walks up to him and tries to tell the dead man a bad joke," Kiritsugu answered in tandem, earning a smirk from the man behind him.

"So what brings you to Cairo, business or pleasure?" the man asked, his voice gaining a tone of seriousness to it.

"Business," Kiritsugu answered. "And no, I'm not here to kill you."

"I like hearing that," The man said as he got up from his table to sit across from the magus killer. "Last thing I want is to go up against a monster like you." The man said as he signaled the bartender to get them a couple drinks. The man has short spiky silver hair and a well goatee. His outfits consist of a black jacket, black t shirt, tan pants and black boots. He has a one blue eye and a pale, almost white, eye.

"It's not like you aren't ready for a fight," Kiritsugu said, examining the drink in front of him.

"Come on; if I was going to kill you, I wouldn't use poison." The man said as he took a drink.

Kiritsugu relented as he took a drink. Unlike the Magus Killer, Sif preferred to kill his enemies in a more direct manner.

If there was anyone that could potentially rival Kiritsugu for the title of "Magus Killer" it would be Sif Ferro. The biggest difference between the two is that while they're both dangerous on their own, Sif has gone to great lengths to ensure that any knowledge of his and his group's existence is kept secret. Only select higher ups of the moonlit world know of their existence. At best, he and his group are only ever referred to as a rumor or a ghost story at best whereas Kiritsugu is highly regarded as the boogey man.

Like Kiritsugu, Sif is only given jobs that are extremely dangerous. He's almost exclusively tasked taking down the worst of the worst.

"So what is it you want to talk about?" Sif asked feeling genuinely curious. If the Magus Killer needed something that he couldn't get himself it must be important. That much was clear from the rare times their paths crossed on jobs.

"Can I assume you've heard of my participation in the recent Grail War?" he asked

"Of course, everyone has. I also heard you had the whole thing in the bag before pissing it away." There isn't a single person who wasn't curious about what happened at the end of the previous grail war. Just about everyone would quite literally do anything to be the Magus Killer's position and rumor has it the grail was his for the taking. Unfortunately there weren't any known survivors of that war to confirm what had happened. Given that Kiritsugu is sitting before him instead of being dead like the rumors would suggest, rumors can't always be trusted.

"Well, I wouldn't put it like that. But it's not too far from the truth."

"Really, what happened?"

With that, Kiritsugu began explaining everything relevant about the fourth war. He explained how the grail had chosen him as the winner. He explained that the grail was possessed by Angra Mainyu, the literal embodiment of all things evil in the world. Continued to explain turning down the Avenger's deal and ordering Saber to destroy the grail.

"That's… quite a story," That's an understatement if there has ever been one. How can anyone process a story like that? Hearing stories about the world coming to an end isn't an unheard of thing in their line of profession, but more often than not it would be greatly exaggerated.

Sif knew a bull shit story when he heard one. It comes with the job. That's how he knew that Kiritsugu is telling the truth. "I'm going to need more to drink." Sif said as he now signaled the bartender to bring him another drink.

"Imagine how much you would need to drink after living through that." Kiritsugu stated dryly before he finished off his drink.

Sif just stared blankly the magus killer. Contemplating his statement, Sif continued to give an unreadable expression for what felt like a couple minutes. "Can I get two bottles of the strongest stuff you have." Sif said loudly to the bartender.

"You really think that's enough?" Kiritsugu asked quizzically.

"It's enough to get started. Honestly, I'm surprised you aren't drunk right now."

"Sometimes, so am I."

"So the grail turned out to be a doomsday weapon and you destroyed it, what happened next?"

"A portion of Fuyuki was destroyed thanks to the curse contaminating the grail." Kiritsugu answers solemnly. That day will always be the worst that he has ever had. Losing two of the three people that mattered the most to him in the same day along with causing the deaths of all those people is something that still haunts his dreams. "I was also cursed by Angra Mainyu. As we speak, that curse is slowly killing me."

"Holy shit," Sif said as he sat back in his seat. "So when I made that joke earlier… "

"You were more on the nose than you thought."

"Has any ever told you that you have the worst luck of all time?"

"No has ever needed to." Kiritsugu said as he stared blankly at his empty glass. If he didn't know any better, he would have thought that his origin is something along the lines of bad luck or misfortune. "That brings me to why I'm here."

"Let me guess, you want help lifting that curse?" Outside of his work as a mercenary, Sif is a bit of history buff with a personal interest in Middle Eastern Lore. He's heard some stories of Angra Mainyu and has a vague idea of which country the stories originate from. He's not an expert on removing curses but he would be valuable for research purposes.

"No, I've already come to terms with what will happen to me. And honestly, dying doesn't bother me in the slightest. With all the people I've killed, it's the least I deserve." Kiritsugu admitted, shocking his companion. Most, if not every, magi in this era wouldn't hesitate to kill any number of people if it was for the sake of guaranteeing results. Some would even do it on a whim without batting an eye. For the most part, Sif is no different.

To hear someone who is as efficient as THE Magus Killer admit that he deserves death for what's he's done is a sobering experience.

"Ok, so what do you want?"

"When the fire broke out I… I spent I don't know how long searching for anyone that could've survived. When I was about to give up I found a young boy named Shirou. He's the first person in my life that I can honestly say I've saved. Not only that but I feel like saving him somehow saved my soul." Kiritsugu couldn't help but smile at the memory. It was the only good thing that came out of that day.

Even Sif found the Magus Killer's smile infectious as he was grinning at what he was hearing.

"Since then I've adopted him as my son and started training him in magecraft," he finished.

"Gotta say I'm surprised to hear that. You've never been a fan of the magus way of life."

"Trust me, he twisted my arm until gave in."

"Who would have thought you of all people has such a soft spot for kids." Sif couldn't stop himself from laughing at his own words. Through his laughter he failed to notice that Kiritsugu wasn't laughing along with him.

Those words only served to make Kiritsugu think back on his times with Illya. Iri would always make jokes about how their daughter had him wrapped around her little finger. She wasn't wrong either, all Illya had to get her way was give him the puppy eye look or throw a small tantrum and Kiritsugu would cave.

It's why his failing to keep his promise to Illya is still something that haunts him. Sure she's safe in the Einzbern castle, but she'll be forced to live a life of isolation. More than likely, Acht will go out his way to convince Illya that he had abandoned her. There's still no telling what else the old homunculus will do her.

"That brings me to what I'm here for." Kiritsugu said with such seriousness that it caused Sif to become more serious as well. "I have maybe a few years left in me. I'm trying to train Shirou in everything I know," Sif knew what that meant. Both are, at their cores, instruments of war and death. Death is all they know and taking lives is what they're good at.

Sif couldn't believe what he's hearing. Kiritsugu has never been someone to care for the magus lifestyle. From the few times the two mercenaries have cross paths, it became clear to Sif that Kiritsugu only sees magecraft as a tool to be used. For him to say that he wants to teach his son everything he knows is saying that he intends to teach Shirou to become a mercenary just like him.

Kiritsugu has made it clear how happy he was to save Shirou. How Shirou was the first person he truly saved. And now he wants to send his son down the same path.

"I need your help. I want you help Shirou finish his training as a magus." The look of seriousness and conviction told Sif just how serious he is. People like Kiritsugu don't make rash decisions. They don't act without calculating every possibility. They only act the upmost certainty.

"So you want me train your son to become someone like us?" Sif couldn't begin to describe his disappointment. There way of life is one only leads to one thing. Regret. No matter how many people they've inadvertently saved, all the lives lost because of their actions still haunts both mercenaries. "Why?"

"To protect him." Kiritsugu answered, causing Sif to glare at the Magus Killer.

"Our skills aren't for protecting people. They're for killing, that's it."

"You're right. It's thanks to my skill that I made so many enemies." Kiritsugu said; the look in eyes only became sharper at his words. It's the same look from his past whenever he sets a plan in motion. "Enemies that won't think twice about going after Shirou for revenge. Thanks to the curse that's killing me, I'm no longer capable of operating at my full strength. I can't go after each one of them myself and it's unreasonable to ask you to do so on my behalf."

Unfortunately, everything that Kiritsugu said is true. Doing so would be the same as making a good portion of the moonlit world his enemy. Sif is a lot of things but crazy isn't one of them. Well, not Kiritsugu levels of crazy.

"I've already began teaching him the basics of magecraft. Even if I stopped his lessons now, he'll push forward and learn on his own. Unfortunately it won't be enough. It never is."

"There has to be another way? Why not just change his name? You already live in Japan, it can't be that much more work for someone like you to have him disappear." Sif tried to reason, there had to be another way.

"I've thought of that. But the problem is that that plans has too many unknowns. It's the same as leaving everything to chance and hope everything will work out."

There is a commonly accepted, yet unspoken, rule amongst all mercenaries that nothing should be left to chance. Even the mercenaries and enforcers of the moonlit world that would rely on luck would do everything they could to mitigate luck as much as possible. To the more experienced, things such as Murphy's Law became a basic expectation.

If someone isn't prepared to deal with the worst case scenario, they deserved death. While cruel, it's the cold reality of their world. A reality that everyone has to accept if they want to survive.

"Ok, so you want me to train you're son," Sif summarized the point of this conversation. "But the one thing I'm having trouble understanding is why come to me?" It's a fair question. While collaborations between magi families are not unheard of, a family very rarely allowed their children to be taught and trained by another. "You and I operate in two entirely different ways. At our cores; you and I are fundamentally opposite in terms of how we operate."

"That's why I picked you. You aren't like other magi. I don't know how Shirou will develop as a magus. I want to make sure his bases are covered. My knowledge is highly specialized and is more suited for someone like me. The last thing I want is for Shirou to turn out as I have." Kiritsugu answers. The thing that scares him the most is Shirou turning out the same way he has. Unfortunately; that me be unavoidable thanks to his son's dream of becoming a hero of justice.

Kiritsugu is an expert at reading people, it's part of what has made him so efficient at his job. When the magus killer told his son about his desire to be a hero that saved everyone; Shirou had a look of true amazement. When he declared that he would follow in his father's footsteps, Kiritsugu just brushed it off as something a kid says without fully understanding the meaning.

The more time the two spent together, Kiritsugu could see that Shirou was serious. He saw the same determination in his adopted son that he had when he was younger. His son's determination left Kiritsugu feeling both scared for his son's future and proud of what he wants to do.

"One last question, why should I help you. What's stopping me from killing you and selling off your son to the highest bidder? You already admitted to me that you aren't capable of doing the things you once were."

There was an uncomfortable silence between the two mercenaries. They simple sat there as they stared each other down.

"Professional courtesy," Kiritsugu said as he smirked at Sif. "Last I checked, you still owe me for Croatia."

"Tch," of all the times to pull an 'I owe you,' the magus killer had to do it now. "You really are a bastard, you know that?" Sif complained, earning an amused chuckle from his companion. "Fine, I do owe you a hell of a favor." He said as he reached for the bottle nearest him. "Just think, a kid being trained by both the Magus Killer and the Wolf of Italy. Wonder what kind of monster he's going to become."

"No matter the route be picks in life, at least he'll be prepared." Kiritsugu said as he ignored the monster comment.

"Alright, let's get going." Sif said as he finished his drink before slamming it on the table, earning a confused look from Kiritsugu.

"And where is it you want to go?"

"To meet this boy of yours," Sif said. "If he's going to be my student, I want to know what he can do."

Huffing in exasperation, Kiritsugu should have seen this coming. What kind of mercenary jumps into a job before learning of all the details first? "Alright fine, but please try not to scare Shirou too much."

 **Time Skip**

After taking a small detour, both Mercenaries arrived at Kiritsugu's home.

"Wow, didn't think you would live in a place like this." Sif said as he took in the sight of the Magus Killer's home.

"I'm just going to pretend I didn't hear you say that." Kiritsugu said as he walked through the front doors with Sif following right behind him. Walking into the living room, Kiritsugu was welcomed to the usual sight of his son in the kitchen cooking dinner with Taiga sitting at the table, flipping through the channels on the TV in an attempt to pass time.

Seeing the door open, Taiga was the first to notice Kiritsugu walk in. "Oh Kiritsugu, you're back sooner than I thought," she said, earning the attention of Shirou.

"Hello to you to," Kiritsugu said sarcastically. "Don't know why you're so surprised, I said I would be back in a couple weeks."

"That's because you're usually gone for at least a couple months at a time." Shirou said as he came out of the kitchen. "Who's your friend?"

"This is an old associate of mine, Sif," Kiritsugu introduced his companion.

"Oh, I'm an associate huh?" Sif said as he pretended to be hurt by the Magus Killer's words. "And here I thought that were friends after everything we've been through."

Kiritsugu would have made some kind of remark, but something caught his attention. That something is the black eye his son had. "Shirou, what did I tell you about getting into fights?" He asked his son sternly.

"I know what you said, but I had to this time. Those bullies wouldn't leave this kid in my class alone." Shirou said in attempt to defend his actions.

Hearing those words causes Kiritsugu to sigh. No matter how many talks he has with his son, Shirou is determined to keep getting into fights with bullies. Don't get him wrong, Kiritsugu is proud that his son is willing to stick up for those in need. He just wishes Shirou would be smart about his actions. "We'll talk about this later."

"I see why I'm here" Sif says slyly to Kiritsugu.

"Shut it"

"I'm sorry, I forgot to introduce myself." Shirou said as he bowed to the newcomer. "I'm Shirou; it's good to meet you."

"Oh, you're a polite one," Sif said amusingly as he stuck out his hand. "The names Sif Ferro, it's good to meet you to Shirou."

After introductions, everyone sat down to enjoy dinner. Sif was surprised by how good the food is. Afterwards, Taiga left to return home for the night, leaving the others to themselves.

"Now Shirou, let's see how much you've progressed." Kiritsugu said. At the moment, him, Sif and Shirou are standing in his shed. It's become the place Shirou became the most comfortable in practicing magecraft and since has become his unofficial workshop.

Hearing this, Sif reached into one of the bags he brought with him and pulled out a knife with various runes engraved into it. Sif has already been given an idea of what kind of thaumaturgy that Shirou has been training in so far. Tracing is by no means anything special. It's considered a very basic form of magecraft that most magi would rather no waste their time on.

Seeing the knife, Shirou closed his eyes before focusing on his magic circuits. **"Trace, on,"** Shirou said as a bright light appeared in his hand. As it dissipated, a copy of the knife Sif was holding appeared in the redhead's hand.

Taking the knife, Sif closely examined it. Carefully examining the weapon, the mercenary came to a single conclusion; Kiritsugu didn't give his son enough credit. The replica Shirou had made isn't a perfect copy, but it was damn close. The knife is a far better copy than someone that's an amateur with no history of magecraft should be able to make. Factor in that Shirou has only been training for a few months at best and Sif could say that he is genuinely impressed.

Taking the copy of the knife for himself, Kiritsugu looked over his son's copy. He knew what Shirou was capable of before he left. Seeing him progress so much time gave him mixed feelings. He has a good idea of how Shirou was able to do it, unfortunately that meant Shirou was overdoing it again. He'll have to put that lecture off to another time. "Good job Shirou, you must have been working really hard while I was gone."

Smiling at his father's praise, Shirou rubbed the back of his head sheepishly. "Yeah, I wanted to surprise you when you got back."

"Well, your hard work paid off. That's for sure. " Sif said as he put the original knife away. Taking his bag and rolling it out on the floor, it revealed to be full of various types of mystic codes. "Let's see what else you can replicate."

One by one Shirou worked his way through each mystic code. With each attempt, Sif got a better idea of what Shirou was capable of. So far, the redhead has proven that weapons such as whips, hammers, and shields were far too complicated for him. Even simpler clothing based mystic codes were too much. Alternatively, Shirou seemed to be adept at projecting every bladed weapon the mercenary had. Interesting enough, the boy was also talented at projecting the bows that Sif had brought.

"So, how did… I do" Shirou asked, his forehead was dripping with sweat as he sat on the floor. Clearly, tracing and projecting so many weapons in a row was still too much for him.

"You're doing great Shirou," Kiritsugu said as he handed his son a bottle of water. "We're almost done," he said as he handed a simple wooden bat to Shirou. "Let's see how far you've improved with performing reinforcements."

Nodding at his father's words, Shirou takes the bat in both of his hands. Putting all of his focus on the bat, the redhead starts pouring mana into the bat. **"Trace On,"** he says as mana started pouring mana into the bat.

As soon as the spell was finished, Shirou hands the bat to father. Kiritsugu had to admit that he's impressed. The bat seemed to be as tough as one made with a very dense metal. Handing it over to Sif, the mercenary came to a similar conclusion. Speculation is good and all, but a weapon that just looks good is useless.

Slamming the bat into the ground, Sif was curious to see how it would hold up. Sure enough, the floor around where the bat had impacted had shattered. The bat itself was slightly dented but in rather good condition. "Not bad kid, pretty good for a novice like you. You still have plenty of room for improvement, but that's to be expected." Sif complemented, ignoring the glare he was getting from Kiritsugu.

"Did you really have to test that bat in here?!" Kiritsugu asked angrily. Of all the things that he must take care of, fixing the damn floor in his shed is the last thing the magus killer wants to deal with.

"Quit complaining, I'll fix it later." Sif dismissed, not really caring of the damage he caused.

"Mr. Sif, if it isn't too much trouble then can you take a look at the support beam? It's starting to rot." Shirou asked, earning curious looks from both adults before him.

"Shirou, how do know that?" Kiritsugu asked.

"Well, I tried that spell you told me about that lets me see what's wrong with things." Shirou asked.

"You mean structural grasping?" Kiritsugu asked, getting a nod of confirmation from Shirou.

"Sure Shirou, I'll take a look at it later." Sif said, grinning at the redhead. Tracing, Projections, Reinforcements, and Structural Grasping. Each one of these are are considered basic thaumaturgy at best. Oh well, it may not be much but it's something at least.

"Um; Dad, didn't you tell me that I shouldn't show other people my magecraft?" Shirou asked. Kiritsugu has been adamant about how important it is to keep magecraft a secret. And bringing some stranger, to Shirou at least, to see what the redhead is capable of seemed unusual to him.

"I did, but this is a special situation," Kiritsugu said as he kneeled before Shirou.

"Really, why?"

"You see; like I mentioned before, Sif is an old acquaintance of mine. We've crossed paths multiple times before I retired. He's trained many people in magecraft and I asked him to help train you."

"Yeah; you see, I owe your old man here a huge favor so I'm going to be your new teacher."

"Why can't you teach," Shirou asked his father.

"That's because when it comes to magecraft I only know the bare minimum and specific spells that aided me in my old job," Kiritsugu tried to explain. "Don't worry I'm still going to teach you what I can. However, Sif here is far more qualified to help you grow as a magus. Especially given your… special circumstance." He finished, successfully easing his sons worries while gaining a curious gaze from his mercenary companion.

"What do you mean by special 'circumstance'?" Sif asked. Despite how long the trip to Japan took, Kiritsugu was rather reluctant when it came to certain sensitive information. Specifically, what Shirou's origin and elemental affinity is.

"You'll find out what I'm talking about soon enough. In fact, we might as well get this over with." Sif understood what Kiritsugu was getting at.

It's time for him to learn what was Shirou's element and origin is. There are a variety of ways to learn of these things. Performing the test, Sif understood why Kiritsugu was tight lipped about this information. Both the origin and element were unique to say the least. The simpler of the two was Shirou's element, or more accurately elements. His elements are sword and fire. Having two elements, while rare, is far from unheard of. Even Kiritsugu had two himself. The sword element though is incredible rare; in fact, Shirou may be the only person with an elemental affinity like that.

What was truly unusual is Shirou's origin. Yet again, it would be more accurate to say origins. Both were rather unusual. The first of the two happened to be sword. Unfortunately; this made Shirou an incarnation. Incarnations are the epitome of rare. So rare in fact, that the Clocktower wouldn't hesitate to slap an incarnation with a sealing designation and spend the rest of their lives being experimented on. The second origin is curse. While there may be a small handful of people within the Clocktower with similar origins, the fact that Shirou has two is dangerous.

Now it made sense why Kiritsugu wanted, no he needed, help in training Shirou. If word of Shirou's specific conditions were revealed to the moonlit world, there's no telling how many people would get killed just to get to the redhead. Not only would the Clocktower be after him, but the Church, various Apostles, everyone of Kiritsugu's enemies that are still alive and any mercenary looking to make a huge profit.

If it wasn't for the fact that Sif owes Kiritsugu a huge favor, even he would sell the boy off. Damn professional courtesy getting in the way of profit.

"Shirou, that's enough for now. Why don't you go rest inside the house? Your dad and I need to talk." Sif said as he focused intently on the Magus Killer.

Hearing the tension in the mercenary's voice, Shirou complied and quickly left the two alone.

"Why the hell didn't you tell me that Shirou had two origins?! Do you have any idea what this means?!" Sif demanded an answer. Of course, someone like Kiritsugu would have thought this through. But how can anyone just let someone discover a bombshell like this without the slightest heads up.

"Because I knew you wouldn't believe me," it's a fair enough explanation. To the best of their combined knowledge, there has never been a case where someone had two distinct and separate origins in recorded history.

"Of course, I wouldn't," Sif said as he pulled a pack of cigarettes from his jacket pocket. Lighting it, he tried to process everything he has just learned. Incarnations have an extremely limited range of what type of magecraft they can learn. Alternatively, it's because of what they are that they can perform spells that no one else can perform themselves. Incarnations are also capable of making huge advances in thaumaturgy that any magus would dream of. "How does something like this even happen?" Sif questions after he exhales a cloud of smoke.

"I have a theory, though I have no way proving it," Kiritsugu said as he pulled out his own pack of cigarettes. Lighting one for himself, he couldn't help but hope that his theory is wrong. If it does turn out to be true, then the curse that is afflicting him is far crueler than Kiritsugu could have ever imagined.

Sif noticed how quiet Kiritsugu had become. It was a type of silence that told him that the magus killer knew exactly how this happened. "Ok, out with it." Sif said, noticing that Kiritsugu didn't react. Damn, he really does have one hell of a poker face. "Clearly you know something and if you want my help then you're going to have to tell me."

"Like I said, it's only a theory right now," what a pain, this situation was always bound to become hassle from the start. "Unless you have someone in mind who can properly test this theory without harming Shirou, it's a moot point."

"Fine, we'll talk about it later," Sif relented. Unfortunately, the list of things they are going to have to discuss is only getting longer. "Jeez, two origins and he's an incarnation on top of all of that. You really have to be the luckiest and unluckiest person there is." Sif said as he exhaled another cloud of smoke. "What's next, are you going to tell that Shirou has a noble phantasm?" he joked, failing to notice just how quiet Kiritsugu had become.

"So, do you have any more questions, or can we get down to why we're here?" Kiritsugu asked to quickly change the subject. Sif is bound to learn just how on the nose his joke is, he just didn't need to learn right away.

"Yeah, I have just one question. Are you sure you want to go through with this? This is your last chance to change your mind." Sif questioned with an utterly serious expression.

"Are you having second thoughts?"

"Of course, before you were asking to train Shirou to protect him from the enemies you made. Now, if things go to hell and word gets out about what Shirou is, it'll be him against almost the entire moonlit world."

"There's a chance that'll happen anyway. My 'shit luck' doesn't just affect me, it affects those I care about. If word does get out, then he'll need to be ready." That's his answer, that's clearest confirmation that Sif is going to get and it's the only one he needs.

Professional courtesy in the moonlit world is a peculiar thing. If Sif declines, then professional courtesy dictates that he would take Kiritsugu's secret, and by extension Shirou's, to the grave. That is, if Sif declines.

Decades ago; in a small town some distance away from Croatia, Sif was hired to take out an apostle. Unfortunately, things went from bad to worse. By the end of the job, Sif and his team, teammates that he trained himself since they were kids and considers them to be his very children, were about to become that bastard apostle's lunch or playthings. Which was worse, he didn't know. As quickly as things went to hell, things had turned against the apostle.

With a giant explosion, the building they were all in had begun to collapse on their heads. Instead of dying, they were all dazed in the aftermath of the explosion. Before the smoke cleared a loud 'bang' could be heard. When the smoke had finally cleared, the apostle was dead on the floor with his brains scattered across the room. Behind the apostle's corpse was none other than the magus killer himself with a pistol in hand.

Sif is no fool. He knew for a fact that Kiritsugu's only purpose for being there was to kill the apostle. Saving them was merely a professional courtesy and nothing else.

Thanks to his pride and gratitude, Sif has no choice but to accept Kiritsugu's request. "You're lucky I owe you. You wouldn't be able to afford my fee otherwise." Sif said as he stomped out his cigarette.

"Thank you," Kiritsugu said as he bowed. It was the only response he could think of to say. In his life, he could count the number of people he's been thankful to on a single hand. "If there's anything I can do to repay you just say it."

"Don't worry about it, I owe you one anyways," Sif said as he waved his hand dismissively. "From one father to another, I understand wanting to protect your kid."

"Still, this goes beyond what I've done for you."

"Like I said, don't worry about it." Sif said as he noticed the troubled look on Kiritsugu's face. "Fine, if it makes you feel better than just buy me a drink and we'll call it even."

What Sif interpreted as Kiritsugu wanting to make things even between them was far from what the magus killer is feeling. True this decision we'll make Shirou far more prepared to handle whatever comes his way. But this decision means that Shirou is no longer someone that he has saved.

This decision may as well lead to Shirou following the same path that Kiritsugu went down. Knowing his son's desire to help people and become a hero of justice was concerning to say the least. If that desire isn't taken care of sooner than later, Shirou will turn out just like Kiritsugu in all the wrong ways. What's worse is that the young redhead is just as stubborn and determined as his father. Unfortunately, Kiritsugu won't have enough time to steer his son away from living that life.

It'll be up to Sif to show Shirou just how flawed that lifestyle is. Will it be enough, who knows?

But there is one question left that is eating away at Kiritsugu. 'Is this the right choice?'

 **And there it is, the prologue to my new story. I've recently got into the fate universe and been wanting to write a story for it for a while now.**

 **The idea for Shirou to have to two different origins and elements came about more recently, though I wouldn't say it was a spur of the moment decision. Unfortunately, I'm still in the early planning phase for this story so I don't know if I will keep or remove it later. It does offer a lot of opportunities for some internal conflict for Shirou, but it can make things too complicated and confusing. Let me know what you think. Should it stay or be removed.**

 **As for the pairing, it's still undecided as of now. Right now, I'm either going to pair Shirou with either Rin or Saber. There is a possibility for a harem, but right now nothing is set in stone yet.**

 **So, what did you think? Like it, hate it, want less exposition. Let me know.**

 **If you have any questions, feel free to ask however you want.**

 **Anyways, I need to get back to work on my other story. Till next time**

 **Mreh**


End file.
